The present invention relates to food patty forming machines. The invention particularly relates to an improved mold plate for a food patty forming machine.
Food patty forming machines are described for example in U.S. Pat. Nos. 3,952,478; 4,054,967; 4,182,003; 4,608,731; 4,541,143 and 4,329,828, and PCT published application WO 99/62344.
In one type of food patty forming machine a mold plate, having patty shaped cavities, is reciprocated between a fill position and a knock out position. In the fill position, food product is delivered into cavities. The cavities are located above or below a food product delivery apparatus. Within the food product delivery apparatus, the food product, such as ground beef or ground poultry, is pumped by a plunger through a manifold and then upwardly or downwardly through a fill slot and into the mold cavities, forming patties.
A breather plate is arranged above or below the mold plate on a side opposite the delivery apparatus. The breather plate includes breather holes which communicate or express air out of the mold cavities while food product is being filled into the cavities from above or below. The breather holes are located at a position. above or below the cavities that is distant from the position of the fill slot, so that a uniform patty shape can be achieved as the air within the mold cavities and within the food product is expelled through the breather holes. During filling, the food product delivered through the fill slot impacts against a solid wall portion of the breather plate directly opposite the fill slot, as the food product advances forward toward the breather holes. After filling of the cavities, the mold plate is then shifted to the knock out position where the mold cavities are remote from the breather plate and the fill slot. The patties are then knocked out of the cavities by a knockout mechanism.
The present inventor has recognized that food patties formed by the aforementioned food patty forming machine have a tendency to form a compressed area of food product above or below the fill slot due to the pressure of the food product filling the mold cavity. The compressed area forms a ridge on the finished patty. This ridge constitutes a region of more dense food product which leads to nonuniform cooking of the patty. FIG. 5 illustrates such a patty 148 having the ridge 150.
The present inventor has recognized that it would be advantageous to provide a food patty forming machine which overcame the above mentioned draw back and produced a food patty having a uniform food density and thickness.
The invention contemplates an improved food patty forming machine of the type having a reciprocating mold plate having at least one cavity which is filled with food product from a fill slot open to one side of the cavity. The improvement comprises the use of first breather holes remote from the fill slot and second breather holes located close to the fill slot.
According to the invention, locating second breather holes close to the fill slot, particularly at the fill slot, or trailing the fill slot (xe2x80x9ctrailingxe2x80x9d or xe2x80x9cleadingxe2x80x9d referring to the direction of movement of the mold plate from the filling position to the knock out position) is particularly effective when used in addition to the location of the first breather holes leading the fill slot, and act to make uniform the density of the food product within the mold cavity.
As food product is filled into the mold cavities, air is forced through both the first breather holes and the second breather holes. However, since the first breather holes have an aggregate open area greater than-the second breather holes, a uniform filling of the cavity, and a uniform food patty is achieved. The second breather holes are sized sufficiently to relieve pressure within the cavity during filling to eliminate the ridge otherwise present on the finished patty.
The breather plate includes return channels on a side thereof opposite the mold plate. Any food product particles which pass through the first and second breather holes are collected and returned through the return channels to a food product collection area to be recycled within the food patty forming machine.
Numerous other advantages and features of the present invention will become readily apparent from the following detailed description of the invention and the embodiments thereof, from the claims and from the accompanying drawings.